Combustion gas recirculating steam and air injector means for furnaces



March 7, 1950 J R BUTLER R 2,499,814

COMBUSTION GAS RECIRCULATING STEAM AND AIR INJECTOR MEANS FOR FURNACESFiled May 23, 19.45

JNWWWM MV Patented Mar. 7, 1950 COMBUSTION GAS RECIRCULATING STEAM ANDAIR INJECTOR MEANS FOR FUR- NACES Joseph R. Butler, Chicago, 111.

Application May 23, 1945, Serial No. 595,311

2 Claims.

My invention relates to smokeless combustion of fuel in furnaces inconnection with steam boilers. It has for its object the means forbreaking up stratification of combustion gases by induced recirculationof these gases through a conduit or conduits located in furnace wallsand the reintroduction of these gases without further dilution withexcess air at a point where the temperature of the incandescent fuel bedwill insure their proper combination for efficient combustion.

Also it provides the means for metering the amount of air over firewhere the hydrocarbons are being distilled off rapidly such as whengreen coal is being added to fuel bed.

My invention relates to the provision of an injection device forinjecting a circulating medium, or media, such as high velocity steam orair, or both, or a varied mixture and velocity, into the furnace tocirculate or re-circulate lean or rich gases, etc.

Another advantage of my invention resides in the provision of meteringmeans for controlling said injection device.

Another advantage, among others, is the provision of such a device insuch a manner as to provide simple access for inspection and repair, andat relatively low cost of manufacture.

Further advantages and objects of my invention will appear and bebrought out more fully in the accompanying drawings, in which:

Fig. 1 is a vertical sectional view of a standard boiler furnace showingmy invention applied thereto.

Fig. 2 is a detailed sectional view on the line 22 in Fig. 1.

Fig. 3 is a detailed sectional view on the line 3-3 of Fig. 1.

Fig. 4 is a detailed sectional view on the line 4-4 of Fig. 1.

Referring to the drawings, I have shown a furnace for a standard steamboiler [0, having grate H, and a front fuel door l2.

Also provided is an ash pit I3 in the front wall 14.

Also shown is the fire brick wall [5, in which are mounted the watertubes 16.

I have also shown a smoke chamber ll leading to the chimney.

In the front wall I have provided an anchor plate 18, secured to thewall by bolts [9, or other suitable means.

The anchor plate I8 is adapted to secure in a bore |8a in the front wall14, a gas circulating device, 20.

The gas circulating or re-circulating device 20 in the form shown has asteam injection pipe 2|, clearly illustrated in Fig. 2, located in anairsupply tube 22.

The circulating device 20 is also provided with an interior meteringinlet opening 23 in the airsupply tube 22.

Also provided in the air-supply tube 22 is an exterior metering inletvalve 24.

The afore-mentioned pipe 2i and supply tube 22 are mounted in a casing25, mounted in tm'n in the bore [8a of the furnace.

Also provided is a metering gage 26 and a handle 21; and, in addition, asteam surface valve 28, admitting steam to the steam injection pipe 2|.

Mounted in refractory blocks 29 is a duct 30 leading into the furnace topermit injection of the steam and air.

There are also provided circulating ducts 3| leading to the meteringopening 23.

It is believed that the operation will be manifest without detaileddescription, but, in short, such a device may be mounted in a standardfurnace, and air or steam may be admitted into the fur--' nace, and maybe metered to suit.

When the steam is injected into the furnace, rich or lean gases may bedrawn into the ducts 3 I and through the opening 23 to be again injectedinto the furnace and be circulated and re-circulated over and over asdesired.

By this means the stratification of combustion gases will be broken upand insure substantially efiicient and smokeless combustion.

It will be manifest also that by the means provided, the amount of airover a fire where the hydrocarbons are being distilled off rapidly, suchas when green coal is being added to the fuel, may be metered.

Also, by the means that I have provided, there is easy access forinspection and repair.

The air-supply tube 22 and the casing 25 may be provided with cut-outs32 and 33 respectively, which may amount to as much as of thecircumference of the tube or casing.

Around these cut-outs, a space 35 may be formed by removing some of thetile or brick.

This may be filled with acoustical packing such as asbestos or spunglass, or other suitable material 36, for reducing or eliminating anyundesirable sound, if such should be found to exist.

In order to keep the packing in place there may be provided a cage 37 oflathing, or other suitable material, about the casing 25.

It will be apparent that the circulating device may be placed atpractically anywhere in the furnace.

While I have illustrated and described the preferred form ofconstruction for carrying my invention into effect, this is capable ofvariation and modification without departing from the spirit of theinvention. I, therefore, do not wish to be limited to the precisedetails of construction set forth, but desire to avail myself of suchvariation and modifications as come within the scope of the appendedclaims.

Having thus described my invention, whatI claim as new and desire tosecure by Letters Patent is:

1. In a furnace having walls and a fire box, the combination, whichcomprises an injector positioned in a wall of the furnace anddirected'toward the combustion area of the fire box, a housing for saidinjector having air inlet means positionedon the outside of the furnacewall, adjustable closures for said air inlet means, said housing alsohaving openings positioned-within the furnace wall communicating withthe interior of the furnace and adapted for drawing hot gases of thefire into said injector for reinjection into the furnace, adjustableclosures for the reinjection openings, a single manually operable meansadjusting the adjustable closures of the reinjection openings and alsothe openings of the air inlet means from the exterior of the furnace,and sound vibration absorbing meansencircling a portion of the injectorand within said wall and combustion area of the fire box.

2. In a furnace'having walls and a fire box, in combination, an injectorassembly arranged in a Wall of the furnace and operably communicatingwith the combustion area of the-said fire 4 box, said injector includinga housing, a steam injecting pipe located within the housing, an airsupply pipe concentric with the steam injecting pipe, valve meansarranged exteriorly of the combustion chamber and efiective to admit airinto the said air supply pipe, other valve means for admitting productsof combustion from the combustion chamber into the pipe, and sounddeadening means encircling and concentric with a portion of the injectorassembly, said sound deadening means being located within a portion ofthe. said furnace wall,

JOSEPH R. BUTLER.

REFERENCES CITED Thefollowing references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 400,709 Piggott Apr. 2, 1889479,771 Walters July 26, 1892 609,225 Briney Aug. 16, 1898 618,011 MacyJan. 17, 1899 747,007 Smith Dec. 15, 1903 783,998 Doyle Feb. 28, 1905906,967 Triggs Dec. 15, 1908 1,066,041 Parsons July 1, 1913 1,310,173Callery July 15, 1919 1,671,448 Plassmann May 29, 1928 1,729,763 DeFlorez. Oct. 1, 1929 1,766,534 Prat June 24, 1930 1,860,366 Lucke May31, 1932 FOREIGN PATENTS Number Country Date 17,302 Great Britain July9, 1902

